Telephone-call instrument.



vPATENTEI) JUNE 14, 1904.

E. W. E. TOMPSON, DEGD. v n.11. Torreon. ADnIMAsTnATnIg. TELEPHONE GALL INSTRUMENT.

APPIIUATION FILED HAY 18l 1903.G N0 IDDEL. V

2 SHEETS-SHEET 2.

PatentevdlJ une 14, 1904.

PATENT OFFICE.

EDV-ARD W. E. TOMPSON, OF BROOKLINE, MASSACHUSETTS; RUTH I-I.

kToMrsoN ADMINISTEATRTX oE DECEA SED.

SAID EDWARD IV. E. TOMPSON,

TELEPHONE-CALL INSTRUMENT,

SPECIFICATION forming part of Letters Patent No. 762,364, dated June 14, 1904.

Application filed May 18,1903.V serial No. 157,743. No model.) l

To a/ZZ whom. t may concern:

Beit known thatI, EDWARD W. E. ToMrsoN, of Brookline, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in Telephone- Call Instruments, of which the following is a specication.

The object of the invention is to give a signal by ringing a bell or otherwise at any desired telephone only wherev there are two or more on the same circuit or party-line. I attain this object by the mechanism shown in the accompanying drawings, in which- Figure l is a plan of the entire mechanism. Fig. 2 is an elevation of the auxiliary battery and call-bell. Fig. 3 is a vertical section of part of the machine on line l 2. Fig. 4 shows four instruments on one main circuit having connections with two electric batteries land the operators key. Fig. 5 is a view of the entire mechanism and means of actuating lever L. -Fig. 6 shows lever L and connections in detail. v

Similar letters refer to similar parts throughout the several views.

The mechanism of this invention is described as follows: The frame b', supports b3 I# M, and the cylinder of pneumatic valve D are attached to a suitable base. Vheels R S and disk A are attached to shaft F. Wheels R S have fifteen teeth each; but more or less p2, the upper portion of said lever movingV forward and backward. Propelling-pawl J is attached to the upper end of leverL by pin p, the free end of pawl J moving upward-and downward. With each forward movement of lever L pawl .I engages a different tooth of wheel R and rotates the shaft F, wheels R S, and disk A. Check-pawl K is attached to support by a pin allowing its free end to move upward and downward, engaging in succession each tooth of wheel S as it rotates-and preventing backward movement of shaft F.

The wheel S and disk A may be omitted and the pins hereinafter referred toinserted inl wheel R and check-pawl I( adapted toengage the teeth of wheel R.

The piston of'pneumatic valve D, connected with arm B by rod I-I and link I, has a valve opening outwardly which allows air to escape freely as the piston descends. Asmall opening in the piston admits air slowly as the piston rises. The pneumatic valve retards the upward movement of arm B and gives time to check it before terminal Pis brought into contact with terminal O. Any suitable retarding device may be used. Weight E gives downward movement to arm C when arm B is free and if unchecked brings terminals P and O into contact, thereby closing the local circuit. Terminal P, attached to arm C, rises and descends with it. Terminal O is fixed to support M. Terminal P is connected with one pole of local battery N by wire X. Terminal O is connected with the other pole of local battery N by wire Z, which passes through the electromagnet of the signal-bell Y, so that signal-bell Y rings while the local circuit is closed. The circuit to the local battery is normally open. Pins T V W are inserted in one side of disk A, projecting so a's to engage arm B of the circuit-closer B C. As disk A is rotated aprojecting pin engages the free end of arm B, forcing it downward and raising the free end of armC. When arm B is forced to its lowest position, the pin slides off and arm B is raised by weight E. If disk A ceases to rotate as soon as arm B is released, arm C closes the local circuit. If disk A continues to rotate after arm B is released, another projecting pin arrests the movement of arm B and prevents the closing of the local circuit. Any signal electrically operated may be substituted forl bell Y. Valve D prevents B from rising quickly and gives ample time to rotate A, and thereby check B before the local circuit is closed.

Means of actuating the lever L and operating thc instruments may be described as follows: The electromagnet d g, the bindingserews fu w, the spring It, and support for thumb-screw a/ are attached tothe base of the instrument. The wires X'1 Z2 connect n and n', respectively, with the main circuit. Bindandswings the upper end of leverf in the y opposite direction, forcing spring backward.

W hen the Vstrong current ceases to pass through the electromagnet di g, spring /t forces lever f forward and swings armature f avv'ayfrom core ,r/. Spring /1/ is of sufcient strength to resist the action of weak currents used for operating telephones. When in normal position, spring I., pressing against lever f', holds armaturef away from core g. Pressure of spring /L may be regulated by thumbscrew d. Spiral spring /L is attached to the upper part of leverL and pulls it forward. Tension o f spiral spring /L may be regulated by thumb-screwe2, to which it is attached. Leversf and'L are `connected by link l, which slidesfreely on pins if pi when one of the upper extremities of said levers approaches the other. l/Vhen armature f, attracted by core g, swings lever f/ backward, lever L and pawl J are drawn backward by link Z, spring /a/ is extended, and pawl J engages a tooth of wheel R. Vhcn lever f is pushed forward by spring t, lever L is released from tension of link Z, spring L draws forward lever L and pawl J, and shaft F, wheels R S, and disk A are rotated one tooth.

. F ig. 4 shows the main circuit to strong battery N2 through. wires X2, operators key C', Wire X3, electromagnets of instruments at stations l 2 3 4, and return-wire Z', this circuit being normally open; also, circuit to battery N, used when talking over the line, through wire X, operators key C, wire X3, electromagnets of the four instruments above mentioned, and return-wire Z', this circuit being normally closed. Telephones may be connected with the main circuit at the several stations. Said instruments being set for use, arms B of the several circuit-closers are in positions to be set free, as follows: at station l when disk A is rotated one tooth by ratchet-wheel R, at station 2 when disk A is rotated two teeth, at station 3 when disk A is rotated three teeth, and at station 4 when disk A is rotated four teeth. The several instruments on the same circuit move simultaneously. To set the mechanism of the instruments in motion, two movements of the key C/ are necessary. Depressing key C breaks the circuit to battery N and closes-the circuit to battery N2, sending a strong' electric current over the main circuit. Raising key C when depressed breaks the circuit to battery N2 and shuts off the strong current. Moving key C' once downward and once upward causes wheel R to rotate one tooth.

An operator having four instruments properly adjusted and connected With four dierent telephone-stations on the same circuit desiring to call No. 3 must work-that is, depress and raise-key C three times in quick succession. Each time the key is worked the wheels and disk in every instrument rotate one tooth. The first time key C is worked projecting pin on disk A in No. l releases arm Band circuit-closer B C is set in motion. Projecting' pins in Nos. 2, 3, and 4 press arms B in those instruments downward. The second time key C is worked arm B in No. 2 is released and circuit-closerB C is set in motion. A projecting pin in No. l obstructs arm B and prevents the closing of the circuit to local battery N, attached to that instrument, and projecting pins in Nos. 3 and 4 The third time key press arms B downward. C is worked arm B in No. 3 is released and circuit-closer B C is set in motion. A projecting pin in No. 2 obstructs arm B, and projecting' pins in Nos. l and 4 press arms B downward. Having Worked his keyv the number of times necessary to calll No. 3, the operator must wait for the instrument at that station to give the signal, which it does as follows: Disk A having ceased to rotate, arm B, released from pressure by projecting pin, is unobstructed, and circuit-closer B C automatically closes the circuit to auxiliary battery N, and signal-bell Y is rung by the electrie current from battery N until the circuit is broken. Having allowed time for the signal to be given, the operator must work his key twice more to set the several instruments on the main circuit for future use. The fourth time key C/ is worked arm B in No. 4 is released and projecting pins in Nos. l, 2, and 3 press arms B in those instruments downward. 'The fifth time key C is worked a projecting pin obstructs arml B in No. 4 and projecting pins in Nos. 1, 2, land 3 press arms B in those instruments downward and leave each instrument ready for the next call. To call a station, key C must be worked in quick succession the number oftimes corresponding to the number of the station desired. Time must then be allowed for the'instrument to give its signal, after which the operators key must be worked the number of times then necessary to set the several instruments on the line for future use. For every call the operators key C must be worked once for each instrument on the circuit and once to maintain open circuits to the several local batteries of all the instruments.

IOO

I make no claim to the invention of electrobattery, or bell.

What I do claim as my invention, and desire to secure by Letters Patent of the United States, is

l. In a telephone system a telephone -call instrument a normally open local circuit, including an auxiliary battery and a signal-bell; a circuit-closer adapted to bring the terminals of said circuit in contact, and cause said bell to ring, a pneumatic valve, aweight, a propelling-lever, a propelling-pawl, a checkpawl, a ratchet-wheel rotatable in one direc-- tion by said propelling-pawl, a ratchet-wheel controllable by said check-pawl so that it may rotate in one direction only, a disk with projecting pins adapted to engage and controlV said circuit-closer and so adjusted as to cause said circuit-closer to bring said terminals in contact only when said disk is rotated by the proper ni mber of movements of said propelling-paw and a rotatable shaft to which said wheels and disk are attached; in combination with a strong battery connected with the main line, and having a normally open circuit, for operating telephone-call instruments, aweaker battery connected with the main line, and having a normally closed circuit, for operating telephones, a main-line electric circuit including a plurality of telephone-call instruments and telephones in different localities or stations, a circuit changer or key adapted to control the circuits to batteries connected with lsaid main line; each telephone-call instrument having an electromagnet operated from the source of electric p ower, a movable armature with lever, a spring with thumbscrew, a link connecting said' armature-lever with said propelling-lever, a spring to move said propelling-lever in one direction, and a thumb-screw to regulate tension of said spring; and a source of electric power to operate.

2. In a telephone system a selective apparatus for causing a signal to be given at the station desired, consisting of a propelling-lever, apropelling-pawl, a check-pawl,a ratchetwheel rotatable in one direction by said propelling-pawl, a ratchet-wheel that may rotate in one direction only, controllable by said check-pawl, a normally open local circuit having terminals adapted to be brought in contact, and including a local battery and signalbell; a circuit-closer adapted to bring the terminals of said local circuit in contact and cause ward movement of said arm, a weight at` tached to the other arm of said circuit-closer, a disk with projecting pins, adapted to engage and control said circuit-closer so that the same may bring the terminals of said local battery in contact only when said disk and pins without intermission make the number of movementsiappropriate to call the station at which said disk is located, a rotatable shaft to which said wheels ,and disk are attached, in combination with a main circuit, an electric battery, an operators key controlling electric currents over said main circuit, and means for actuating said propelling-lever, said means being operated by the current from said battery.

3. In a telephone system a selective apparatus, consisting of a circuit-closerl having two arms attached to a movable shaft, a weight attached to one of said arms, and adapted to closer,'a rotatable disk with projecting pins,

so placed as to engage said circuit-closer, and control its movements; said circuit-closer, weight, valve and disk being adapted to cause a signal-bell to ring, only when the station at which they are located is called; in combination with a swinging armature with lever, a main line, an electromagnet connected with said Vmain line to attract said armature, a spring to repel said armature, a propellinglever with spring attached, a thumb-screw to regulate tension of said spring, a link connecting the armature-lever with the propellinglever, a ratchet-wheel and propelling-pawl to rotate said disk in one direction, a second ratchet-wheel and check-pawl to prevent backward movement, a local circuit including an auxiliary battery and signal-bell, an electric battery connected withv said main circuit, and a key controlling said main circuit.

In testimony whereof I have aHiXed my signature in presence or' two witnesses.

EDWARD w. n. ToMPsoN.

IOO 

